A 26-Year-Old Woman, Gravida 1 Para 0, at 8 Weeks

A 26-year-old woman, gravida 1 para 0, at 8 weeks gestation is brought to the emergency department by her husband after saying that she wants to die and threatening to hang herself.  In the past few weeks, the patient has become increasingly depressed and uninterested in doing anything.  She spends most of her time in bed and sleeps 14 hours a day.  She has lost 4.5 kg (10 lb) due to refusal to eat or drink.  The patient says that food is "polluting my body and allowing my demon child to grow."  She has a long history of poorly controlled bipolar disorder with episodes of depression and mania.  The patient made 2 suicide attempts during her teens.  She takes no medications currently and is not under the care of a therapist or psychiatrist.  The patient appears thin, with dry and chapped mucous membranes.  Physical examination is otherwise normal.  During examination, she makes monosyllabic responses and has slowed movements.  The patient is admitted to the psychiatric unit.  Which of the following is the most appropriate next step in management?

A) Electroconvulsive therapy
B) Fluoxetine
C) Lithium carbonate
D) Valproate
E) Venlafaxine